In light of the success of assertiveness training in effecting behavioral change in children, the need has arisen for a reliable, externally-valid instrument to pinpoint children who might benefit from assertiveness training and to measure the behavioral change resulting from such training. The primary purpose of the proposed study is to provide external validation for the Children's Action Tendency Scale (Deluty, q979) using behavioral observations in naturalistic settings. The Children's Action Tendency Scale (CATS), a self-report questionnaire assessing how children aged 6-12 would behave in the face of frustration, provocation, and conflict, yields aggressiveness, assertiveness, and submissiveness scores. In the proposed study, the correspondence between children's self-reported CATS scores and their actual interpersonal behavior during a wide variety of school activities will be assessed. A secondary purpose of the proposed project is to explore the situation-specificity of assertiveness in grade-school children. The study will examine whether boys and girls who tend to respond assertively when frustrated, proved, or aggressed upon are comparably assertive in less conflictual, more "positive" interpersonal situations (e.g., when giving or receiving a compliment, when initiating or terminating a social interaction). In addition, the proposed study will explore the influence of gender and age on both "negative" assertiveness (e.g., in response to frustratgion or provocation) and "positive" assertiveness. The behavioral ratings, which will be obtained as part of the CATS validation procedure, will be analyzed to assess sex and developmental differences.